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EVAP System, Checking For Leaks

Special tools and workshop equipment required 

NOTE:

Replace seals and gaskets when performing repair work.

Leak checking

-- Using a Smoke tester, check the Evaporative Emission (EVAP) canister system for leaks.

NOTE:

Always follow the manufacturers directions for the proper installation and operation of the Smoke tester being used.

If a leak is detected:

-- Check the fuel filler cap seal for damage and for proper installation. Replace if necessary.

-- Check the seals under the locking flanges and the union nuts are properly tightened on the fuel tank.

-- Check all hose connections of the fuel supply system and replace or repair any leaking lines.

-- Check all hose connections of the EVAP system and replace or repair any leaking lines.

-- Repair or replace any damaged component.

If no leaks are found in the EVAP and Fuel Supply System:

-- Erase the DTC memory if a DTC was set. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .

-- Perform a road test to verify repair.

If a DTC was set and does not return:

Repair complete, Generate readiness code. Refer to READINESS CODE DESCRIPTION .

-- End diagnosis.

If the DTC does return and no leaks are found in the EVAP and Fuel Supply System:

-- Check the DTC memory for any DTC codes pertaining to the EVAP and Fuel Supply Systems. If a DTC is stored, perform the diagnostic test procedure for the suspected component. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .

End diagnosis.